SRC/zgeqrt2.f(3)           Library Functions Manual           SRC/zgeqrt2.f(3)

NAME
       SRC/zgeqrt2.f

SYNOPSIS
   Functions/Subroutines
       subroutine zgeqrt2 (m, n, a, lda, t, ldt, info)
           ZGEQRT2 computes a QR factorization of a general real or complex
           matrix using the compact WY representation of Q.

Function/Subroutine Documentation
   subroutine zgeqrt2 (integer m, integer n, complex*16, dimension( lda, * )
       a, integer lda, complex*16, dimension( ldt, * ) t, integer ldt, integer
       info)
       ZGEQRT2 computes a QR factorization of a general real or complex matrix
       using the compact WY representation of Q.

       Purpose:


           !>
           !> ZGEQRT2 computes a QR factorization of a complex M-by-N matrix A,
           !> using the compact WY representation of Q.
           !>

       Parameters
           M

           !>          M is INTEGER
           !>          The number of rows of the matrix A.  M >= N.
           !>

           N

           !>          N is INTEGER
           !>          The number of columns of the matrix A.  N >= 0.
           !>

           A

           !>          A is COMPLEX*16 array, dimension (LDA,N)
           !>          On entry, the complex M-by-N matrix A.  On exit, the elements on and
           !>          above the diagonal contain the N-by-N upper triangular matrix R; the
           !>          elements below the diagonal are the columns of V.  See below for
           !>          further details.
           !>

           LDA

           !>          LDA is INTEGER
           !>          The leading dimension of the array A.  LDA >= max(1,M).
           !>

           T

           !>          T is COMPLEX*16 array, dimension (LDT,N)
           !>          The N-by-N upper triangular factor of the block reflector.
           !>          The elements on and above the diagonal contain the block
           !>          reflector T; the elements below the diagonal are not used.
           !>          See below for further details.
           !>

           LDT

           !>          LDT is INTEGER
           !>          The leading dimension of the array T.  LDT >= max(1,N).
           !>

           INFO

           !>          INFO is INTEGER
           !>          = 0: successful exit
           !>          < 0: if INFO = -i, the i-th argument had an illegal value
           !>

       Author
           Univ. of Tennessee


           Univ. of California Berkeley


           Univ. of Colorado Denver


           NAG Ltd.

       Further Details:


           !>
           !>  The matrix V stores the elementary reflectors H(i) in the i-th column
           !>  below the diagonal. For example, if M=5 and N=3, the matrix V is
           !>
           !>               V = (  1       )
           !>                   ( v1  1    )
           !>                   ( v1 v2  1 )
           !>                   ( v1 v2 v3 )
           !>                   ( v1 v2 v3 )
           !>
           !>  where the vi's represent the vectors which define H(i), which are returned
           !>  in the matrix A.  The 1's along the diagonal of V are not stored in A.  The
           !>  block reflector H is then given by
           !>
           !>               H = I - V * T * V**H
           !>
           !>  where V**H is the conjugate transpose of V.
           !>

       Definition at line 126 of file zgeqrt2.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0                SRC/zgeqrt2.f(3)